Choose from four mixing heads, and add the solid state speed controller. The low speed high-torque models feature a Jacobs style chuck that will accept shafts from 5/8" to 3/8" . The high speed low-torque models use a hollow through shaft and precision hand tightened collet. This allows positioning the propeller at any depth without moving the mixer head. The controller is connected to the mixer head via a 6 foot 3-wire cord keeping electronics away from possible spills. Controller offers precise speed control with a 100:1 adjustment range. Motor speed is maintained within 10% despite changes in line power or load. For 110V, 50/60 Hz.